I have read in many places that if the alignment of the plates is lost (for example when removing them to clean, and then reassemble them) the information is irretrievable. Is there no way to realign it as it was in the factory?

I have read everything, people who say it is impossible, and people who say that it is possible to recover the alignment.

What's the true about all this ?

The truth is that some makes/models are extremely sensitive to platter alignment whilst others aren't.
For models that are sensitive to platter alignment, when it's lost, it's game over, IMHO.

_________________
http://www.northwind.gr
SandForce SSD Recovery
Ransomware Reverse Engineering - NoMoreRansom! partners

+1

_________________
Digitalsupport Data Recovery
https://digitalsupport.dk

And how do the recover data companies when they have to take out the platters to clean ?. If the model is very sensitive to alignment they not try?

They keep it a secret so that competitors don't do it for less.

_________________
Luke
Recovery Force Data Recovery

Maybe I'm a perfectionist, but this was painful to watch. It also doesn't answer how to realign platters that are moved individually, as was asked.

_________________
Luke
Recovery Force Data Recovery

...you found a video showing a widely-known method of keeping platters aligned while moving them to another base.

It takes another level of expertise to be able to remove platters from a multiple-platter drive INDIVIDUALLY, clean them, and then reproduce original platter alignment and eccentricity.

In response to OP's question, if platter alignment is completely lost, the original alignment is as likely to be reproduced as getting a Seagate F3 to initialize with a different PCB/ROM.
With the right tools however, many drives can be made to initialize off the first platter then platters can be imaged individually.
...not with all drives though as previously stated. With Seagates in the Crawford family if original platter alignment and eccentricity is lost, you may be able to image the bottom platter (with the right tools) but beyond that you're hosed.

Why?

I have a very strict rule here; never put your hands over the platters unless absolutely necessary. Even with gloves on, touching the platters can cause issues. So, unless you need to be working with the spindle, there is no reason to move your hands over the platters.

Spend $100 on a hard drive stand from Apex Tool Lab or a fancier version from HDD Surgery for a little bit more.

_________________
Luke
Recovery Force Data Recovery

Well,
This Guys LAB Is a Pile Of Dust ,He Might Be Good In Repair Of MACS He Is Absolutely Nowhere Close To a DR Tech .Did i Hear Someone Say We Can Work With Primary Platter And Then Others Will Be a Hassel In F3 Seagate ,Not With Me Buddies While Platter Cleaning ,Few Cases Are Still There With Me In The Main LAB .I Am Slowly Feeling Little Better But Still Not Too Much In Office But i Miss My Community And Youtube Channel

_________________
Regards
Amarbir S Dhillon , Chandigarh Data Recovery Labs [India]
Logical,Semi Physical And Physical Data Recovery
Website-> http://www.chandigarhdatarecovery.com

I use the video method to change the plates from one record to another, but with small differences.

What scares me is giving heat to a disc because in my opinion it can produce deformations in the dishes, just as with the temperature the magnetic fields can deteriorate.

The papers I stick to the adhesive tape before putting them on the plates.

_________________
Is Earth an intelligent being?

I have an experience with Hitachi hdd. Totaly lost platter alignment . It was work .I never tired another one. But I will try . lol.

_________________
A Recovery Service In Turkey . Veri Kurtarma Türkiye https://www.digitalverikurtarma.com
Donor Drives hdddonormarket.com